It is common to sell several types of fish in the form of fillets already deboned. These fillets are obtained by cutting the fish along each side of the backbone by hand, with a knife or using apparatus or machines. Each of these machines or apparatuses is designed for separating the backbone, avoiding damage to the integrity of the fillets. However, the presence of nerve bones (“pin bones”) obliges further boning for rendering an acceptable product). Therefore, after cutting the fillets, some bones (pin bones) remain adhered or, in some cases, they remain inserted in the fillets and shall be extracted.
This problem is present during all types of fillet processing and is particularly complex in countries where fillets production is intended for the most demanding markets, implying compliance with the highest quality standards.
The quality highly relates with the time elapsing from the fish death until the product arrive to its destination place, comprising the time spent in processing and packaging.
U.S. Pat. No. 5,525,101 discloses a device for removing pin bones comprising a roller including bone capturing means. Once captured, the bones are extracted applying a traction force.
U.S. Pat. No. 7,247,086 relates to an apparatus and procedure for extracting pin bones from fish fillets, employing the basic principle of the '101 patent above. The procedure comprises detaching the pin bones from the meat using vibrations, and then, extracting the pin bone using only enough traction force in order to pull out the pin bones, thus preserving its integrity, without damaging the interior and exterior of the meat. The apparatus comprises a vibration generator, a boning device, and means transmitting said vibrations from the generator to the boning device.